“Hemp-derivative (Cannabis sativa L.) food products containing trace levels of Δ-9-tetrahydrocannabinol (THC) are proposed for consumption in Australia and New Zealand; however, it is unclear whether use of these products will negatively affect existing drug screening protocols.

Consumption of low-content THC oil does not result in positive biological assessments.

It is therefore highly unlikely that ingestion of products containing these levels of THC will negatively impact existing region-specific drug driving enforcement protocols.”

https://www.ncbi.nlm.nih.gov/pubmed/29408718

https://www.sciencedirect.com/science/article/pii/S0379073817305492?via%3Dihub